After seeing headline after headline about how sitting is killing you, you finally did it. You got a standing desk.

Well, you might want to sit down for this. A new study from the Human Factors and Ergonomics Society says that prolonged standing is pretty bad for you, too.

The short-term effects of prolonged standing include fatigue, cramps, and back aches, but the long-term consequences can be even more grave.

For the small study, Ph.D. candidate Maria Gabriela García at ETH Zurich had two age groups (18 to 30 and over 50) stand for five-hour stretches with brief rest breaks and a 30-minute lunch.

Tests revealed that the participants' muscles, regardless of age, were fatigued more than 30 minutes after the standing experiment ended — but their mental perception of discomfort didn't last that long.

As Garcia explains it, “Long-term fatigue after prolonged standing work may be present without being perceived ... this long-lasting muscle fatigue may contribute to musculoskeletal disorders and back pain.”

So what are you supposed to do? Trade off sitting and standing. Extremes are bad. Moderation is good. Oh, and remember to take short walks throughout the day, too!